TriZetto Provider Solutions: 3,433,965 individuals affected

Revenue cycle management company TriZetto Provider Solutions filed this year's largest breach report to date in February 2026. The company, owned by IT company Cognizant, handles more than 2.5 billion healthcare transactions annually..

According to a breach notice provided to the Maine Attorney General's Office, TriZetto first became aware of suspicious activity within its systems on Oct. 2, 2025. Upon discovery, the company launched an investigation and notified law enforcement.

Further investigation revealed that an unauthorized party had been accessing records related to insurance eligibility verification transactions since November 2024. TriZetto found that the affected data potentially included names, addresses, Social Security numbers, health insurer names, dates of birth and other demographic and health insurance information.

TriZetto said in its breach notice that it immediately took protective measures to safeguard its systems.

QualDerm Partners: 3,117,874 individuals affected

QualDerm, a healthcare management company that operates a network of over 150 dermatology and cosmetic surgery practices across 17 states, suffered a breach in December 2025.

On Dec. 24, 2025, QualDerm detected unauthorized activity on certain systems and immediately launched an investigation, which determined that an unauthorized individual had removed information from QualDerm's systems.

The impacted information included patient and doctor names, medical record numbers, email addresses, treatment and diagnosis information and health insurance information.

QualDerm said it was unaware of any attempted or actual misuse of the impacted information.

"As part of our ongoing commitment to the privacy of personal information in our care, we are reviewing our existing policies and procedures regarding information security, as well," the notice stated.

QualDerm reported the breach to OCR in February 2026.

Nacogdoches Memorial Hospital: 2,507,073 individuals affected

Nacogdoches Memorial Hospital, a 226-bed hospital in Nacogdoches, Texas, reported a breach to OCR in March 2026. NMH became aware of a data security incident on Jan. 31, 2026, when a cyberattack enabled an unauthorized party to compromise its computer network.

NMH said it immediately notified law enforcement and activated its incident response plan. The impacted information included names, addresses, phone numbers, Social Security numbers, medical account numbers, health plan beneficiary numbers and photographs.

"NMH takes the security of all information in its systems very seriously and wants to assure its patients that it has taken steps to prevent a similar event from occurring in the future," a notice to patients stated.

"This includes implementation of remediation measures to prevent recurrence, to strengthen NMH's network security, enhancing NMH's cyber preparedness through additional awareness training, and updating NMH's procedures."

Navia Benefit Solutions: 2,151,330 individuals affected

Navia Benefit Solutions, a national benefits provider, filed a breach report with OCR in March 2026 after discovering suspicious activity within its environment on Jan. 23, 2026.

Further investigation revealed that an unauthorized party had accessed and potentially acquired information between Dec. 22, 2025, and Jan. 15, 2026. The breach involved names, Social Security numbers, dates of birth, phone numbers, email addresses and health plan information.

Navia said it has since reviewed the security of its systems, notified impacted individuals and assessed its policies and procedures to reduce the likelihood of a similar event in the future.

NYC Health + Hospitals: 1,800,000 individuals affected

NYC Health + Hospitals, the largest municipal healthcare system in the U.S., discovered a cyberattack on its computer network on Feb. 2, 2026. The health system launched an investigation and determined that an unauthorized actor accessed its systems between Nov. 25, 2025, and Feb. 11, 2026, copying files in the process.

"Although the investigation is ongoing, it appears that the unauthorized actor may have gained access to NYC Health + Hospitals systems due to a security breach at a third-party vendor," the health system said in its March 2026 notice.

The breach involved health insurance information, medical and biometric information, billing and claims data, Social Security numbers and financial account information.

In response to the breach, NYC Health + Hospitals said it deployed additional protective technologies across its network, reset credentials for compromised accounts and updated its remote access management policies.

The health system is now facing scrutiny from lawmakers over the breach. Senate Health, Education, Labor, and Pensions Committee Chair Bill Cassidy (R-La.) sent a letter to NYC Health + Hospitals CEO Mitchell Katz on June 4, 2026, seeking answers about the scope and impact of the cyberattack.

OpenLoop Health: 716,000 individuals affected

OpenLoop Health, a white-label telehealth infrastructure vendor, disclosed a breach that occurred on Jan. 7, 2026. The company offers licensing and credentialing, practice management and provider staffing services to digital health companies.

According to a breach notice provided to the California Attorney General's Office, OpenLoop discovered that an unauthorized party had removed certain information from its systems during a cyberattack.

OpenLoop confirmed that the unauthorized access had been terminated. It also  engaged external cybersecurity specialists and arranged complimentary credit monitoring for impacted individuals. It said it would continue to enhance its security posture.

ApolloMD Business Services: 626,540 individuals affected

ApolloMD Business Services, an Atlanta-based healthcare management services organization that provides clinical staffing, practice management and administrative support, experienced a breach in 2025 that it reported to OCR in February 2026.

ApolloMD first became aware of suspicious activity within its IT systems on May 22, 2025, later determining that an unauthorized actor had accessed and potentially acquired information pertaining to patients treated by ApolloMD's affiliated physicians.

The impacted data included names, diagnoses, dates of service, treatment information, health insurance information and Social Security numbers.

ApolloMD notified 11 physician practices of the breach between July and September 2025.

Erie Family Health Centers: 570,000 individuals affected

Illinois-based Erie Family Health Centers experienced a data breach that potentially exposed patient names, email addresses, Social Security numbers, biometric data, prescription information, taxpayer ID numbers, passport numbers and health insurance information.

Erie discovered the breach on Jan. 27, 2026. It launched an investigation that determined an unauthorized party had gained access to Erie's systems between Dec. 10, 2025, and Jan. 27, 2026.

"Erie takes its obligations with respect to the privacy and security of information seriously. We have taken steps to address the incident and are committed to protecting the information entrusted to us," the notice to patients stated.

Erie provided patients with information on safeguarding their information and signing up for complimentary credit monitoring services.

Minnesota Department of Human Services: 303,965 individuals affected

In January 2026, the Minnesota Department of Human Services disclosed a third-party breach to OCR that involved its MnCHOICES system. MnCHOICES is Minnesota's free assessment and support planning system used by counties, tribal nations and managed care organizations to support planning work for individuals who need long-term services.

The breach stemmed from FEI Systems, the vendor that manages MnCHOICES. FEI Systems specializes in providing health IT solutions to federal, state and local agencies. According to the Minnesota Department of Human Services' breach notice, a "provider-associated user" accessed the demographic records of over 300,000 individuals and additional information for 1,206 of those individuals.

The user no longer has access, and there is no evidence that the information has been misused.

"The DHS Office of Inspector General is aware of this incident and has developed data-driven processes to monitor and evaluate billing information, in an effort identify [sic] whether there was fraudulent or inappropriate use of the accessed data," the notice stated.

"If potential fraud is identified, DHS will fully investigate and when appropriate refer those matters to law enforcement."

This breach was the only one in the top 10 that was caused by unauthorized access/disclosure rather than a hacking/IT incident.

North Texas Behavioral Health Authority: 285,086 individuals affected

The North Texas Behavioral Health Authority, a certified community behavioral health clinic, suffered a data breach after learning that a hacker accessed and copied information from its network.

The impacted data included names, Social Security numbers, addresses, driver's license numbers, medical information and health insurance information.

Jill Hughes has covered health tech news since 2021. Her coverage areas include cybersecurity, HIPAA compliance, interoperability, AI and EHRs.